#include <iostream>
#include <iomanip>
using namespace std;

void hello()
{
    cout<< "hello!" << endl;

}
long x (long y,long z)
{
    return y * z;
}
int a()
{
    return 1;
}
int add(int a, int b)
{
    return a + b;
}
float daoshu (double q)
{
    if(q==0)
    {
        cout<<"input error!!!!!!!!!!!"<<endl;
        return 0;
    }
    return  1.0 / q;
}
int main()
{  
    hello();
    cout<< add(1,1)<< endl;
    cout<< 1+1 << endl;
    cout<< a() <<endl;
    cout<< x(100,123)<< endl;
    long k=x(999,999);
    cout<< k << endl;
    cout<< 1.0/4 << endl;
    cout<< daoshu(0) << endl; 

    int a,b,c,d,e; 
    e=1;
    d=1;
    for (a = 1; a < 10; a++)
    {
        c=1;
        for (b = 0; b < a; b++)
        {
            d=c*e;
            cout << c << "X" << e << "=" << setw(2) << d << " " ;     
            
            c++;
        }
        
        cout << endl;
        e++;
    }
    return 0;
    
}